In my previous life as an office drone, I always brown-bagged it because I was too broke thrifty to blow $7 on a soggy ham and cheese from the deli down the street. I Will Teach You To Be Rich points to a great lunch savings calculator; you can play with the values and enter in your own estimate for at-home lunch prices, eating out, how many days, etc. According to my calculations, in five years I saved about $8400. — Wendy Boswell